Air pump



A. BURNAM AIR PUMP Filed March 2. 1 921 Patented Feb.. 19, 1924.

ALLEN .BUE/NAM, 0F SAN ANTONIO, TEXAS, ASSIGNOR 0F ONE-HALF TO C. M. HOOKER, OF SAN ANTONIO, TEXAS.

AIR PUMP.

Application iled March 2, 1921.

To all whom t may concern.'

Be it known that l, ALLEN BURNAM, citizen of the United States, residing at San Antonic, in the county of Bexar and State of Texas, have invented certain new and useful Improvements in Air Pumps, of which the following is a specification.

This invention relates to an improved air pump particularly intended for the inflation of pneumatic tires and has as one of its principal objects to provide a thoroughly eiicient double acting pump which may be manually operated with a minimum of labor.

The invention has as a further object to provide a pump so constructed that packing of air in the passages of the pump will be eliminated while the valves of the pump will quickly respond to any change in direction of movement oi' the pump piston.

A. still further object of the invention is to provide a pump wherein the discharge tube employed may be arranged either near the upper end or lower end of the pump, as may be found most convenient. y

And the invention has as a still further object to provide a pump wherein access may be readily had to the check valves of the pump so that these valves may be easily maintained in proper working order and wherein frail or delicate parts will be avoided to the end that the pump will deliver dependable service in practical use.

y Other and incidental objects will appear hereinafter.

In the drawings:

Figure 1 is a vertical sectional view taken medially through my improved pump.

Figure 2 is an enlarged fragmentary section showing the upper end portion ot the pump cylinder and associated parts.

Figure 3 is an enlarged sectional view showing the lower end portion ofthe pump cylinder and associated parts, and

Figure 4 is a detail perspective view showing one of the closure plugs for the discharge chambers of the pump and the check valve retained by said plug.

In carrying the invention into eiect, 1 employ a base 10 into which is threaded a cylinder 11 and upstanding from the base at one side of the cylinder is a nipple 12. Threaded upon the cylinder at its upper end is a head or cap 13 and depending from said cap at one side of the cylinder is a nipple Serial No. 449,070.

14 alining with the nipple 12. Formed in the base to communicate with the lower end of the cylinder is a short passage 15 entering a discharge chamber 16 opening through the adjacent side of the base below the nipple 12, and establishing communication between said chamber and the nipple is a second short passage 17. Mounted in the chamber 16 to normally close the passage 15 is a spherical check valve 18 and threaded into the chamber is a closure plug 19 provided at its outer end with a head 20 having angularly disposed faces so that a wrench may be applied thereto. rilhis head is also preterably formed with a screw driver slot. The plug is provided with a smooth tapered inner end portion 21 extending across the passage 17, and said end portion of the plug is cored to freely receive a spring 22 bearing between t-he plug and the valve 18 for normally holding the valve closed. In this con nection it is to be observed that air may freely flow through the valve chamber around the tapered inner end portion of the plug and through the passage 17. Formed in the head 13 to communicate with the upper end of the cylinder 11 is a short passage 23 communicating with a discharge chamber 24. Gpening through the adjacent side oiu .the head at the base of the nipple 14 and leading from said chamber 24 into the nipple is a second short passage 25. Mounted in said chamber is a spherical check valve 26 and threaded into the chamber is a closure plug 27 upon which is integrally formed a head 28 having angular faces so that the plug may be easily removed. The outer end portion of the plug beyond said head is formed to provide a nipple or discharge tube 29 and suitably connected to said nipple is an appropriate discharge hose 30. The plug is provided with a tapered inner end portion 31 extending across the passage 25 and cored to freely receive a spring 32 bearing between the plug and the valve 26 for normally holding the valve closed. As will be observed, air may flow through the discharge chamber around the .tapered inner end portion of the plu and through the passage 25. Removably tting at its ends in the nipples 12 and 14 is a discharge pipe 33 coupling the discharge chambers 16 and 24 and snugly surrounding the end portions of said pipe are coupling sleeves 34 threaded into the nipples 12 and 14. These nipples are provided internally with beveled seats while the sleeves are provided at their inner ends with beveled shoulders to eoaet with said seats so that airtight joints will, without the use of pack#` ing, be formed between the pipe and the nipples. Y e

Reciprocable through the head 13 axially of the cylinder 11 is a'hollow piston rod 36 upon the inner end of which is mounted a piston 37T oi appropriate character. The head is formed with a boss to surround the rodl and threaded into said boss is a gland 88 providing an air-tight joint between the rod and the head. Mounted upon'the upper end of ther-rod is a handle 39 held between stop nuts 4t() preferably eountersunk partially in the handle and threaded upon the upper end of the rod to seat against the uppermost ot' said nuts is a cap l1 having a plurality of apertures therein communicating with thev interior of the rod. Fixed within the lower end portion of the rod is a tubular bushing Ll2 and normally seating against said bushing is a spherical check` valve-43. Threaded into the lower end of' the rod isa tubular iollower 44, the lower tween said follower and the valve is a spring l5 normally holding the valve closed. Formed through the head 13 at the base of the upstanding boss thereon isa series of spaced air inlet passages 46 and 'formed within the head to surround the piston rod in concentio relation is a raised annular valve seat 47 having the passages opening therethrough. Depending from the head to snugly surround the piston rod is a sleeve 48 andl loosely surrounding said sleeve is an annular valve 49 upon which is mounted a suitable packing 50 disposed Vto coi'iperaue with said seat. Resting upon the upper end ofthe cylinder 11 and clamped between the cylinder'and the head isaspider plate ai.k and bearing between said` plate and the valve'is a spring 52 encircling the sleeve and normally holding the valve closed. n

Assuming now that the piston 37 is traveling downwardly, it will be seen that air will.

within the cylinder above the piston will be.. expelled through the discharge cl'ianiber and: through the"dischargev hose. Accordingly, as will be seen, air Vwill be expelledV by thev piston at each stroke thereoi. In

tliis'connection, it is to be noted thatr since theV passages 15 and' 25 are short, air will not pack therein to cause delayed opening or closing of the valves 1S and 26 so that these valves will always quickly respond to a change in the direction of movement of the piston.

Attention is now directed to lthe tact thatV theplugs 19 and 27 may be readily removed for displacing the check valves 18 and Consequently, these valves may be readily kept in repair and in proper working order.Y

lFurthermore, Yit is to be noted that theA plugs 19 and 2( may be interchanged. iis` a result, the plugl 2T may be arranged either at `the upper or lower end of the puinp for disposing the discharge hose O'acecrdingly, as may be found most convenient. l

`l-laving thus describedV the what is claimed as new :V

In an air pump, a cylinder, a head closing Y the upper end of the cylinder-and provided with" an air` inlet opening and with an axial dependingV sleeve, a piston slidable in the cylinder-a piston rod extending through the iniv'ention7 l head'and through said sleeve mounting the piston, an air inlet valve associated with the piston, a spider clamped between said head and the cylinder surrounding said sleeve, a valve surrounding the sleeve and slidable longitudinally thereon, anda spring bearing between said spider and the valve normally holding the valve closed to overlie said opening. 'Y n ln testimony whereof.' l ali'x my signature.

ALLEN Bennati. it.' a] 

